Display devices for printed material such as shown in U.S. Pat. No. 3,874,103 employ magnetic devices to maintain visual material within the display area and a bubble member to protect the visual material from inclement weather conditions. Another sign element containing magnetic devices is described in U.S. Pat. No. 3,367,049. Neither of these references describe devices that can be conveniently used as a construction site inspection board since they do not combine features of strength and low cost with proper components useful to the construction trade.